6502.org

I was kind of thinking of starting a new topic on basic test equipment that's relevant to 6502 hobbyists' work, but wasn't sure if it might dishearten those who are not in a situation to even afford the basics. I have other basic equipment besides what I mentioned above, and I can use the 6502 workbench computer (sometimes with peripheral breadboards) to substitute for a lot of other stuff like arbitrary waveform generators, digital scope (with four inputs and four traces a couple of weeks ago—see the pictures below, although I could have stood to at least double the sample rate for the sake of that one trace in particular), audio spectrum analyzer, programmable power supplies and loads with near-microsecond resolution, microcontroller programmer, etc., etc.. This stuff just keeps working for decades, although I've had to spray the contact cleaner into the pot.s and switches on some of the equipment. None of it is dependent on OSs or interfaces that are here today and gone tomorrow. When I worked in applications engineering at a VHF & UHF power transistor manufacturer in the mid-1980's, the lab had about $100,000 of equipment per engineer, back when $100,000 was more money than it is today. I made a couple of small pieces of test equipment for my amateur-radio hobby and calibrated it with the equipment at work. Since then I've worked at two tiny companies, being the only engineer in the company most of those years, companies with a shoestring budget, which is fine with me.


This breadboard was for multiplexing the four inputs to the workbench computer's single A/D converter:

I found a photo on google of my signal generator:
http://www.flickr.com/photos/keithgreen ... otostream/
It has been tweaked by somebody, not much, and it didn't work much, so the tubes are still kinda new...
As for the multimetersthat i have:
http://img535.imageshack.us/img535/8364 ... 73224f.jpg
The left one is a Iskra Unimer31, and the right one is a mystery, it is a Asahi MV570A digital tester it works, it is 1980' era, bought by my father(bought are), i can't find anything on google about it, like it never existed...
I took both this instruments from my father(like some other stuff), since they are reliable, not like those moder cheap-like digital testers, i bought a bunch of them already, and they all died! So i will stick to this old ones. Except it is a bit annoying to change the batteries often on that digital tester, it uses 4x C batteries, and they don't last long(that is the reason i got it so easily )...
As for the soldering iron, i bought a new Weller WHS 40, but the transformer makes an unbelievable noise(is it normal?).
For the power source i bought a cheap MW dc power supply, it died, so i went back to the shop to have it fixed, they gave me a new one, which was not working, so they fixed it again, and since then it has been working.
I bought a Genius G530 Chinese programmer, and it can program almost anything. Since i don't have a scope yet i use an old national Panasonic transistor radio, and i tune to 1MHz, and then i can detect if the clock signal is present... Also i use a double 4040 based frequency divider contraption(with an 2MHz oscillator, so it can also generate a clock), that I have done as a homework in high school(most useful homework ever)...
I also do have a temperature meter from Iskra, it measures from -220, to 800C using a pt100 probe, and i also have a TexasInstruments SR50A calculator as a backup for the modern one...

I was reading about FPGA Signal Tap. It could be cost effective and work.

http://www.dhgate.com/altera-usb-blaste ... 63dde.html

At the end, I think the best way to find a cheap scope is through the local classifieds (as i did, i even got the chance to try it out before i bought it).

Is this scope plenty good?

1 GS/s Digital Storage Oscilloscope + Extras - DS1052E
http://www.adafruit.com/products/681

It is basically an 8 pound $400 scope and the blog post is here:

http://www.adafruit.com/blog/2012/01/26 ... ope-extras

Is there a better scope?

While fixing the issue with the max232, the tip of the scope probe broke(actually i bent in somewhere, and while i was trying to fix it, like many times before, it broke), as a temporary fix i soldered it back.
How do i find a compatible tip, the probe itself is kinda no-name i got it with the scope(HM 512).

Most 'scopes in this league have inputs that look like a 1M resistor to ground, shunted by approximately 20pF. The probe will be made for that, with a capacitance adjustment. Before you use it, put it on the x10 setting and connect it to the oscilloscope's calibration square-wave output, and adjust the trimmer on the probe so the 'scope displays a square wave with flat tops and bottoms.

Edit: You did say tips, not whole probes. In that case you'll probably have to find out who made the probes, since the tips and other accessories won't necessarily be compatible.

The tip unscrews from the probe, I'll shoot a picture tomorrow, in the hope that someone might identify it. There are lots of probe tips on ebay also...

I've been using the SeedStudio Nano thing, it's good for most basic debugging: checking if there are pulses on a bus wire or to see if an IC is powered correctly. Needless to say, for the price you won't get much but it's better than nothing. How about this fella:

http://www.bitscope.net/store/?p=view&i=item+4

I recently bought a Open Workbench Logic Sniffer but it hasn't yet arrived. (Already got a Bus Pirate but that's too slow for looking at CPU busses.) I realise that neither of these is professional quality lab equipment, but they are much more affordable.

Yeah, i still didn't post the picture, the day i was supposed to the forum got hacked, and later i forgot about it, and i soldered the tip back(not perfect but it works), still got to find a new.
I also got a pickit2 clone, and it has a logic analyzer tool, but when i poked into the sbc bus, the sbc froze, it looks like the input impedance of the pickit2 is too low for the bus to drive.

As for that scope that i bought from second hand, it works fine, and it was of great help.

I recently picked up one of these for the storage ability. It works well for $365 (including shipping). I have not tried to use all the features, and it does seem to have some quirks at certain horizontal rates (need to look for new firmware I guess), but for the price it does what I needed it to.